Patches to add support for dark themes

Rivendell has not worked with dark color themes from a factory install; RDAirplay has a fixed background on the log items but uses the system foreground color for text.

This patch modifies rivendell-2.10.1 to support dark themes, such as defaults with KXStudio. It also retains support for the original color theme that rivendell was developed for.

For example screen shots, please goto http://rivendell.danielbair.com/2014/11/30/rivendell-dark-theme-support/